The invention relates to a closure system for containers used for storing or administering substances in the form of liquids, pastes or powders, which system is composed of a cap, provided with a through-hole, and of a closure element, said cap holding the closure element with a force fit and/or form fit on the container, in the area of the opening that is to be closed, by means of an undercut present on the container.
Aluminum caps for dental vials are known from DIN ISO 11 040 part 3 of year 1993. These caps are used to securely close glass cylinders, for example, by means of piston plugs or sealing discs. For this purpose, after the piston plugs or sealing discs have been applied, the caps are fixed on the glass cylinder by means of a deformation process carried out on the cap. Part 2 of the standard describes, among other things, thin sealing discs made of an elastomeric material.